Royal Dutch Shell expects a landmark corruption trial over a Nigerian oil deal to last many months, warning staff of continued critical media coverage in the $1.3 billion case, according to an internal memo seen by Reuters.

Shell’s Legal Director Donny Ching encouraged employees to study an internal web page that the Anglo-Dutch company set up for the case before responding to questions from relatives and friends.

Shell and Italian peer Eni ENI.M are defendants in a Milan bribery trial, now in its early stages, focusing on the 2011 purchase of Nigeria’s OPL 245 offshore oilfield for about $1.3 billion.